Hello, 
I was wondering if there is a way to add georeferenced to .asc file from PRISM to convert it to a raster layer in ArcMap or in R? 
I tried to also add it using R but the crs is NA and when I add the layer to arc map it lets me know that the layer is missing spatial reference info. I should also mention that when the file download from the zip it is a text file for some reason and I added the asc extension to it. 
Any help or suggestions would be appreciated! 
thank you!